Our overall objective is the evaluation of the structure, function, and localization of adenylate deaminase in blood and tissues of man and animals, and its physiologic role in neuromuscular, and potentially other, diseases. This can be subdivided into the following categories: (1) Determination of the enzyme level in normal skeletal muscle, in relation to fiber-type distribution, other enzymes, and subcellular compartments; followed by corresponding analysis of other tissues and blood cells. (2) Comparison, by histologic and solution assay, of levels in patients with myo-adenylate deaminase deficiency (mADD) and other diseases. (3) Purification of the human enzyme from muscle and other tissues for characterization, isozyme distinctions, and antibody generation. Characterization will include MW determination by analytic or density-gradient ultracentrifugation, atomic absorption analysis of metal ion content, and kinetic studies with modifiers and alternate substrates. Isozymes will be evaluated by column chromatography, PAGE, and immuno-diffusion/electrophoresis. (4) Specific antisera will be used to identify and isolate any non-functional enzyme in patients with mADD, and their isozyme source of any residual activity. Clinical diagnosis will be evaluated using the lactate/ammonia exercise test, and, if feasible, by small-needle aspiration biopsy. The genetic mode of transmission will be determined by applying the same procedures to the patients' families. (5) The possible contribution of adenylate deaminase deficiency will be explored for malignant hyperthermia and neutrophil dysfunction syndromes. With regard to urease, concentrated effort will be focused on obtaining accurate subunit and metal ion stoichiometries by accurate measurement, on highly purified enzyme, of nickel content by atomic absorption, native enzyme MW by UC, and subunit MW by SDS-PAGE.